Maker Pro
Maker Pro

Playing a sound clip

QuadU

Sep 24, 2012
1
Joined
Sep 24, 2012
Messages
1
Hello all,

A friend of mine is going to play Santa Claus in Lapland next winter and I'm helping him to make a letterbox for the kids to post their Christmas letters. The idea is that a sound clip is played when a letter is inserted. My first idea was to reuse a cheap mp3 player, upload one song on it and connect its play button to a mechanical switch. However, the problem is that on almost all mp3 players, the play button also acts as pause button. That will cause the clip to pause when e.g. a bad (double) contact is made or when a new letter is posted while the clip is still playing.
I also looked around for small electronic kits, found the perfect solution in following kit:
http://www.velleman.eu/products/view/?id=407028
But I faced the same problem as also here the play/pause connector pin is shared.

Now I'm looking for an (electronic) solution to make sure that after a contact is made, no new contact can be made for x seconds. This ensures that the clip finished playing before a contact towards the play/pause button can be made again...

Can anyone help me with this?
Alternative solutions are welcome as well of course!

Thanks for your help!
 

Harald Kapp

Moderator
Moderator
Nov 17, 2011
13,722
Joined
Nov 17, 2011
Messages
13,722
You can use a monoflop (e.g. based on the 555 timer IC). The monoflop would be triggered by a sensor (mechanical, or optoelectronical) upon insertion of a letter into the box. The output of the monoflop closes the "play" circuit by means of a transistor or photocoupler.
Set the delay of the monoflop to the length of the tune you want to play.
 
Top